Inputting Dynamic Variables

I am trying to organize a set of dynamic variables that can be
modified either by using an input field or by updating the variables
from a file. When updating from a file I use a button.  I have a large
number of variables although in the toy example below I just give 3.
The modules will end up in a private context.  The idea below is that
the function pp[] contains a list of all the variables in a held form.
The list named vals can be obtained by reading from a file with new
values updated from new files.

Below I give an example that works. However, there must be a better
way... Having a ClearAll in a button seems a poor method for getting
back to symbols rather than values.  Any suggestion for a better
approach.?



ReSet[] := DynamicModule[{},
  Dynamic[TableForm[
    Table[InputLine[pp[][[i]]], {i, Length[iv]}]
    ]]
  ]

InputLine[{p_, q_}] := DynamicModule[{t},
  ReleaseHold[ Row[{p, InputField[Dynamic[t]]}] /. t :> q]
  ]

ButtonReSet[] := Button["New values",
  Module[{aa, bb},
   ClearAll[a, b, c];
   aa = ReleaseHold[pp[][[All, 2]]];
   bb = pp[][[All, 1]] /. vals;
   Evaluate[aa] = bb;]]

F[] := DynamicModule[{},
  Dynamic[Plot[a x^2 + b x + c, {x, -1, 1}]]
  ]

ClearAll[pp, a, b, c];
iv = {a, b, c};
pp[] := {{"coff a ", Hold[a]}, {"coff b ", Hold[b]}, {"coff c ", Hold
[c]}};
vals = {"coff a " :> 2, "coff b " :> 3, "coff c " :> 4};
Dynamic[#] & /@ iv

ReSet[]

F[]

ButtonReSet[]

you may use method similar to the one used for bookmarks in manipulate

here is simple example

ClearAll[a, b, c];
vals := {a = 4, b = 3, c = 4};
Save[NotebookDirectory[] <> "\\1.val", vals]
vals := {a = 5, b = 3, c = 4};
Save[NotebookDirectory[] <> "\\2.val", vals]
ReSet[] :=
 DynamicModule[{},
  Dynamic[TableForm[Table[InputLine[pp[][[i]]], {i, Length[iv]}]]]]
InputLine[{p_, q_}] :=
 DynamicModule[{t},
  ReleaseHold[Row[{p, InputField[Dynamic[t]]}] /. t :> q]]
ButtonReSet[] := Button["reset values", vals]
ButtonBrowse[] :=
 Button["browse for New values",
  With[{xfile = SystemDialogInput["FileOpen",
      {NotebookDirectory[], {"val file" -> {"*.val"}}},
      WindowTitle -> "load your settings..."]},
   If[xfile =!= $Canceled, Get[xfile]; vals]], Method -> "Queued"]
F[] := DynamicModule[{}, Dynamic[Plot[a x^2 + b x + c, {x, -1, 1}]]]
ClearAll[pp, a, b, c];
iv = {a, b, c};
pp[] := {{"coff a ", Hold[a]}, {"coff b ", Hold[b]}, {"coff c ",
    Hold[c]}};
vals := {a = 2, b = 3, c = 4};
Dynamic[#] & /@ iv
ReSet[]
F[]
Row@{ButtonReSet[], ButtonBrowse[]}